Clamp for master sheets of printing machines



Dec. 3, 1946. E J, JANKE 411,881

CLAMP FOR MASTER SHEETS OEPRINTING MAcH1NEs- Fila Nome; 1944 'z'sheetS-sheet 1 v j] 4 l Ifremer;

D.3,1946. I C E JJ`ANKE- 2,411,881

CLAMP FOR MASTER SHEETS OF PRINTING MACHINES Filed Nov. 8, 1944 2 sheets-sheet 2 A l1 a f /J l A "//v 204240 4g IVENTOR. fownxn .7: JNK:

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Patented Dec. 3, 1 946 71.

UNITED STATE CLAMP rolav MASTER SHEETS or PRINTING MACHINES Edward J'.- Janke, Cleveland, Ghio, assignor to Ad'dressograph-Multigraphy Corporation, Cleveland, Ollio,y a corporation of Delaware Application November 8, 1944, Serial No. 562,440

12 Claims. 1

The general object of this invention is to provide a veryV simple and at the same time very effective clamping means for holding the ends of a master sheet on a printing drum. l

Another object of the invention is to provide such clamping meansas will enable the mounting of theplate and the Vdemounting thereof within a minimum of time. Still another object is to provide a simple clamp which may hold plates having perforations along one end into which projections of the clamp may extend and to hold with equal facility plates which are impervious.

My clamping means vis adapted kfor holding plates of various materials but is especially well adapted for clamping comparatively thin paper plates', and has its maximum usefulness with plates which are frequently changed, due to its capacity for quick operation.l

To the above ends,` Ilhave provided two clamps mounted vwithin the gap of theV drum for the master sheet,r one vclampY operating vto engage the leading-'end ofthe plate andthe other the trailing end. The leading end clamp, with which this invention is concerned,y anchors that end of the plate tightly inposition, While the trailing end clamp is adapted not only to hold the plate-but to apply tension thereto, to retain it taut about the drum. For the trailing end, I prefer to use a.` clamp of the character described andclaimed in Patent No. 2,165,283 of F. E. Curtis, issued July 11,. 1939, to my assignee, Addressograph-Multigraph Corporation. y

The leading end clamp of this invention is best understood from description hereinafter given .of a preferred embodiment thereof illustrated in the drawings. l

In the drawings, Fig. 1 is a plan of a master sheet drum having myinvention of clamp for the leading. end and also'a clamp for the trailing end; Figi 2**is an end elevationf`ofsuch drum showing the'two clamps; Fig-1` 3`isj an end view on a larger scalefof the leading end clamp and adjacent portiorfsof-'t-he' drum, the clainpbeing shown in'open positiony receiving the rnasterfsheei, and" ready to` clamp the same; Fig. 4f is a cross section through the.) leading end clamp i-n an intermediate location parallel to Fig. k3, as indicated for instance by the line 4`4 on Fig. 1. 'The drum 1:0 is provided with a gap Il Ofcomparatively 'small depth and' small arcuate extent. Within this gap are two ledges` |12 and I3' which constitute'or carrythe anvils for the leading end clamp and the trailing endiclamp respectively.

'Ihe anvil Vledge I2 forl the leading end clamp is p'ferablya plane inset from thev vperiphery of (Cl. 10i-415.1)

, secured to it by rivets` 3i.

, 2 Y the drum surface I5, such surfaces being joined in this region by a fiat surface I6 which makes an oblique angle to a tangent to the drum surface at the point of departure and preferably makes a right angle with the anvil surface I2. At the other end of this anvil surface the gap in the drum provides a surface Il preferably at right angles to the surface i12. f

Secured to the surface continuous hinge. The other leaf 2l of this hinge is adapted to lie parallel with and bear against the surface I2, While the free edge of the leaf may stand close to the surface I6 of'the gap. The two members 2B and 2lA are connected by a continuous hinge rod 22.

The continuous hinge described is of the general type commonly known as a piano hinge.

'Howeven as I use it the ears of both leaves are nal bar 25 extending theflength of the drum, and s" rigidly fastened to the leaf, preferably by counte'rsunk rivets 26.

' Thehinge leaf 2 is shown as extending beyond each end of the drum. .At one end thereis mounted on it an operating lever 30 shown as This operating lever extends to each side of the pivot provided by the pintle 22. At its outer end it isa preferably bent inwardly as shown at 32. To this inwardly bent end is secured a tension spring 35, the other end of which is anchored to a pin 36 carried by the end plate i8 of the drum. There is also indicated in Fig. 1 a spring 31 anchored to the projecting endl of the hinge leafk 2| at the other end ofthe drum,`the inner end of the spring beingA suitably anchored to the drum.

The effect` of the springs shown is to maintain the leaf 2i normally down in the rabbet space provided'by the surfaces l2 and I6 of the drum. When it is desiredv to mount the leading end of a plate in such space a finger pressure on the inwardly projectingv end ofthe lever Si! may tip the hinge leaf 2l back away from the ,anvil into some such position as shown in'Fig. 3 and then f thev plate, indicate-dat A in that'iigure, may be readily'inserted in thev direction of the arrow X.

l1, which is approxiy mately radial of the drum, is one vleaf 20 of a When the finger pressure on the lever, indicated by the pressure-arrow Y, is released the springs swing the hinge leaf into the position shown in Fig. 4. This acts to bend the master sheet abruptly at a, Fig. 4, from the curved surface for more than a. right angle into position along the face of the drum surface IB and to again bend the plate at a.' bythe amount of a right angle into position along the face of the anvil surface l2. These bends cause the plate to be very effectively clamped even though the surfaces engaging it are smooth and the tension springs light enough so that pressure of the operators nger on the lever 30 may readily release the clamp. l

By mounting the hinge leaves 2B and 2l so that the ears of both extend from the leaf in the same direction (that is both toward Vthe right of the leaf, as shown) instead of employing the usual right-and-left hand connection, I cause the hinge axis toilie entirely beyond the anvil I2 but close thereto and nearly in the plane of the anvil, and I leave a succession of aligned ears alternatively of the two hinge leaves beyond the anvil but tangent to the surface Il to which the fixed leaf is secured. This results in a smooth curved surface leading upwardly from the end of the anvil and forming a definite stop for the inserted master sheet irrespective of the angle of opening of the clamp. The master A may accordingly be inserted quickly to the limit of its movement, where its end abuts the continuous hinge with the assurance that it is in proper place and that its edges (which are at right angles to the end) will lie parallel with the ends of the drum.

The inwardly turned end 32 of the clamping lever 3D overhangs the end of the drum surface as indicated in Fig. 4, and stands close to it so that it forms a ready side guide for the positioning of the master sheet.

Finally, as the clamp is readily opened by finger pressure of the operators right hand on the lever Sli he'may very readily and quickly place the master sheet in the position indicated in Fig. 3 by his left hand, and then by releasing the lever efectively clamp the sheet. I-Ie may then by turning the drum cause the sheet to lie along its surface with its other end in position to he engaged and held by the trailing end clamp.

As master sheets are sometimes provided with a row of perforations or perforated ears on their ends intended for hooking over projections in mounting the sheet, I provide a row of hookingprojections 22 on the bar 25 over which such perforated master sheet may Ice-hooked.' As the springs normally maintain the clamp closed such hooks are available and readily accessible within the periphery of the drum as indicated in Figs. Z and 4, so that such sheet'may be hooked onto the projections and then the drum rotated yto bring the trailing end clamp into position for engaging the other end of the sheet.

lIhe trailing end clamp, as shown, is adapted for operation equally well on a thin paper plate originally imperforate (indicated at Ain each figure) or on a plate normally provided with openings or perforated ears on its ends (indicated at B in Fig. l)-as for instance a metal plate shown and claimed in Patent No. 1,957,221v of Allen @t Hartley, issued July 24, 1934, and now assigned to Addressograph-Multigraph Corporation.

As shown, the trailing end. clamp comprises a yoke having a longitudinal bar portion di) extending over the ledge I3 and a pair of end arm portions flI provided with slots llwhich are mounted on pins i3 projecting from Athe -end members of the drum. Tension springs 44 are attached at their outer ends to pins 45 on the end members and anchored at their inner ends to pins carried by the drum, preferably the same pins 36 which anchor the springs of the leading end clamp.

The diagonal direction of the springs 44, and the movement allowed by the slots 42, give the longitudinal bar 40 of the trailing end clamp a tendency to bear against the ledge I3 and to move inwardly along such ledge. The ledge I3 is provided with periodic recesses or pockets I9 and the bar 40 of this clamp has inwardly projecting prongs 48 which register with these recesses. These prongs are spaced in correspondence withv the openings of the perforated plate which is adapted for use in this machine, so that when such perforated plate is bent around the drum with its end overhanging the ledge I3 the prongs will extend through the openings and thus rmly hold the plate on the anvil ledge and also supply a tension thereto.

In the case of an imperforate paper plate these prongs, which come to sharp points, operate to perforate the plate, and pass through it in the same manner as if it were originally perforated in this region. The plate thus is held at the trailing end by the spring pressure of the clamping bar 40 holding the plate on the ledgeA and by the prongs passing through the plate, resulting in the springs 44 maintaining effective tension on the plate.

In securing the trailing end, the clamping bar Il@ is manually lifted away from the ledge I3 by a suitable nger grip. As shown, I have provided for thisy purpose a backwardly bent portion of the plate 49, furnishing a nger ledge, as indicated at 49 in the drawings.

It will be seen that-whether a platealready perforated is used, or an imperforate plate adapted to be kinked by the leading end clamp, it may be mounted at each end in the minimum of time and will thereafter remain in position on the drum under proper tension lduring the printing operation. At the end of the operation the plate is removed with equal facility. The tipping back of the trailing end clampby the finger ledge '4S releases the plate at that'end, and then, after the drum is given half or three quarters of a rotation, the leading end clamp is in position for ready release. If a thin paper plate is used it is not necessary even to. operate the leading end clamp manually, as the platemay be readily pulled out of that clamp by a jerk in a direction away from the drum. In the case of a metal plate, having perforated ears mounted on hooks 28, it may be readily unhooked from such anchorage without paying attention to the clamp.

I claim: 1. The combination of a drum having a gap and a ledge within the gap, a hinge having one leaf secured to the drum andthe other leaf adapted to lie parallel with the ledge or be tipped atan angle thereto, and'means adapted to maintain the latter leaf in contact with amaster sheet between such leaf and ledge.

2. The combination of a drum having a gap and a ledge within the gap offset inwardly from a corner formed by the gap and the periphery of the drum, a hinge having one leaf vsecured to the drum and the other leaf adapted tolie parallel with the ledge or be tipped at an angle thereto, and a spring adapted to press the latter leaf toward the ledge and clamp a master sheet between such leaf and ledge. Y 3. The combination with a drum having a gap,

a ledge within the gap and a surface extending inwardly from the kfree edge of the ledge, a hinge having one leaf secured to said inwardly extendthe drum having also a surface extending inwardly from the free edge of the ledge, a hinge having one leaf secured to the latter surface and the other leaf adapted to stand parallel with the ledge and coact therewith, and a spring acting on the latter leaf tending to maintain it seated on a master sheet bent inwardly over the edge of the gap and then in a reverse direction between the ledge and free leaf.

5. The combination of a drum having a gap and a ledge within the gap, and also having a surface extending from the free edge of the ledge, a hinge having one leaf secured to the latter surface and the other leaf adapted to stand parallel with the ledge and coact therewith, a spring acting on the latter leaf tending to maintain it seated on a master sheet between the the periphery of the drum' when the clamp is' openthereby provide an edge guide for the sheet being inserted.

8. The combination of a drum having a gap, a ledge within the gap, a hinge having one leaf secured to the drum, the other leaf being adapted to coact with the ledge to clamp a sheet between them, a lever secured to such other leaf and extending in each direction from the pivot thereof, a portion of the lever extending inwardly from the pivot being adapted to form a manual operating device for tipping the leaf, a portion extending outwardly from the pivot being bent inwardly at its free end beyond the leaf to provide an edge guide for a master sheet being inserted between the free leaf and ledge, and a tension spring anchored to the drum at its inner end and connected at its outer end with the free leaf.

.9. The combination of a drum having a gap, a ledge within the gap, a piano hinge having its leaves extending longitudinally of the drum, one of said leaves being secured to the drum, the

other leaf being free and adapted to clamp a sheet between itself and the ledge, the ears of ledge and free leaf, and a lever connected to the free leaf and adapted to tip it to enable insertion yof the master sheet in the space between the leaf and ledge.

6. The combination of a drum having a gap, a ledge within the gap', a hinge having one leaf secured to the drum, the other leaf being adapted to coact withthe ledge to clamp a sheet between them, a lever secured-,to such other leaf and extending beyond the pivotal axis thereof to form a manual operating' device adaptedr by inward movement to tip the leaf outwardly, and a spring tending to seat the free leaf against the ledge.

7. The combination of a drum having a gap, a ledge within the gap offset inwardly from the periphery of the drum toleave an abrupt shoulder where the periphery joins the gap and another abrupt shoulder where the offsetting surl said piano hinge forming a stop for a sheet inserted into the space between the ledge and the free leaf when tipped back therefrom.

l0. The combination of a drum having a gap, a ledge within the gap, apiano hinge having its leaves extending longitudinally of the drum, one of said leaves being secured to the drum, the other leaf being freeand adapted to clamp a sheet between itself and the ledge, a spring acting on the free leaf tending to maintain it in' coaction with the ledge, and a lever connected to the free leaf and extending beyond the pivot of the hinge and 4adapted to tip the free leaf away from the ledge,

1l. The combination of a drum having a gap and a ledge within the gap, a hinge having one leaf secured to the drum, the other leaf yadapted to coact with the ledge to clamp a sheet between them, and -outward projections carried by the n free leaf and adapted to project through open- EDWARD J. JANKE. 

